Support EC2 API wildcards for DescribeTags filters

The EC2 API supports glob-style wildcards in filters.

From http://docs.aws.amazon.com/AWSEC2/latest/APIReference/ApiReference-query-DescribeTags.html:

"You can use wildcards in a filter value. An asterisk (*) matches zero or more characters, and
a question mark (?) matches exactly one character. You can escape special characters using a
backslash (\) before the character. For example, a value of \*amazon\?\\ searches for the literal
string *amazon?\."

This patch converts the glob-style regex to a python regex and uses re.match to do the rest. The
approach to the conversion was taken from the python fnmatch library.

Fixes bug #1205099

Change-Id: Ie9cac182faabf50fc0d40480db39a46a7e97fbec
Merge "Support EC2 API wildcards for DescribeTags filters"